/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.wl4g.dopaas.uds.service.elasticjoblite.config;

import java.util.HashMap;
import java.util.Map;

import javax.sql.DataSource;

import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Primary;
import org.springframework.core.env.Environment;
import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;

import com.zaxxer.hikari.HikariDataSource;

/**
 * Dynamic datasource config.
 */
// @Configuration
public class DynamicDSAutoConfiguration {

	public static final String DRIVER_CLASS_NAME = "spring.datasource.default.driver-class-name";
	public static final String DATASOURCE_URL = "spring.datasource.default.url";
	public static final String DATASOURCE_USERNAME = "spring.datasource.default.username";
	public static final String DATASOURCE_PASSWORD = "spring.datasource.default.password";
	public static final String DEFAULT_DATASOURCE_NAME = "default";

	/**
	 * Declare dynamicDataSource instead of default dataSource.
	 * 
	 * @param environment
	 *            spring environment
	 * @return A subClass of AbstractRoutingDataSource
	 */
	@Bean(name = "dynamicDataSource")
	@Primary
	public DynamicDataSource dynamicDataSource(final Environment environment) {
		DataSource defaultDataSource = createDefaultDataSource(environment);
		DynamicDataSource dynamicDataSource = new DynamicDataSource();
		dynamicDataSource.addDataSource(DEFAULT_DATASOURCE_NAME, defaultDataSource);
		dynamicDataSource.setDefaultTargetDataSource(defaultDataSource);
		return dynamicDataSource;
	}

	private DataSource createDefaultDataSource(final Environment environment) {
		String driverName = environment.getProperty(DRIVER_CLASS_NAME);
		String url = environment.getProperty(DATASOURCE_URL);
		String username = environment.getProperty(DATASOURCE_USERNAME);
		String password = environment.getProperty(DATASOURCE_PASSWORD);
		return DataSourceBuilder.create().driverClassName(driverName).type(HikariDataSource.class).url(url).username(username)
				.password(password).build();
	}

	public static class DynamicDataSource extends AbstractRoutingDataSource {

		private final Map<Object, Object> dataSourceMap = new HashMap<>(10);

		@Override
		protected Object determineCurrentLookupKey() {
			return DynamicDataSourceContextHolder.getDataSourceName();
		}

		/**
		 * Add a data source.
		 * 
		 * @param dataSourceName
		 *            data source name
		 * @param dataSource
		 *            data source
		 */
		public void addDataSource(final String dataSourceName, final DataSource dataSource) {
			dataSourceMap.put(dataSourceName, dataSource);
			setTargetDataSources(dataSourceMap);
			afterPropertiesSet();
		}
	}

	public static class DynamicDataSourceContextHolder {

		private static final ThreadLocal<String> CONTEXT_HOLDER = new ThreadLocal<>();

		/**
		 * Get the specify dataSource.
		 * 
		 * @return data source name
		 */
		public static String getDataSourceName() {
			return CONTEXT_HOLDER.get();
		}

		/**
		 * Specify a dataSource.
		 * 
		 * @param dataSourceName
		 *            data source name
		 */
		public static void setDataSourceName(final String dataSourceName) {
			CONTEXT_HOLDER.set(dataSourceName);
		}
	}
}
